package com.nowcoder.community.community.service;

import com.nowcoder.community.community.dao.LoginTicketMapper;
import com.nowcoder.community.community.dao.UserMapper;
import com.nowcoder.community.community.entity.LoginTicket;
import com.nowcoder.community.community.entity.User;
import com.nowcoder.community.community.util.CommunityConstant;
import com.nowcoder.community.community.util.CommunityUtil;
import com.nowcoder.community.community.util.MailClient;
import com.nowcoder.community.community.util.RedisKeyUtil;
import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.security.core.GrantedAuthority;
import org.springframework.stereotype.Service;
import org.thymeleaf.TemplateEngine;
import org.thymeleaf.context.Context;

import java.util.*;
import java.util.concurrent.TimeUnit;

@Service
public class UserService implements CommunityConstant {

    @Autowired
    private UserMapper userMapper;

    @Autowired
    private MailClient mailClient;

    @Autowired
    private TemplateEngine templateEngine;

    @Value("${community.path.domain}")
    private String domain;

    @Value("${server.servlet.context-path}")
    private String contextPath;

    @Autowired
    private LoginTicketMapper loginTicketMapper;

    @Autowired
    private RedisTemplate redisTemplate;

    public User findUserById(int id){
        // return userMapper.selectById(id);
        User user = getCache(id);
        if(user == null) {
            user = initCache(id);
        }
        return user;
    }

    public User findUserByName(String username) {
        return userMapper.selectByName(username);
    }

    /**
     * 注册业务
     * @param user
     * @return
     */
    public Map<String,Object> register(User user){
        Map<String,Object> map = new HashMap<>();

        // 空值处理
        if(user == null){
            throw new IllegalArgumentException("参数不能为空");
        }
        if(StringUtils.isBlank(user.getUsername())){
            map.put("usernameMsg","账号不能为空");
            return map;
        }
        if(StringUtils.isBlank(user.getPassword())){
            map.put("passwordMsg","密码不能为空");
            return map;
        }
        if(StringUtils.isBlank(user.getEmail())){
            map.put("emailMsg","邮箱不能为空");
        }

        // 验证账号、邮箱是否可用
        User u = userMapper.selectByName(user.getUsername());
        if(u != null){
            map.put("usernameMsg","该账号已存在！");
            return map;
        }
        u = userMapper.selectByEmail(user.getEmail());
        if(u != null){
            map.put("emailMsg","该邮箱已被注册！");
            return map;
        }

        // 注册用户
        user.setSalt(CommunityUtil.generateUUID().substring(0,5));
        user.setPassword(CommunityUtil.md5(user.getPassword() + user.getSalt()));
        user.setType(0);
        user.setStatus(0);
        user.setActivationCode(CommunityUtil.generateUUID());
        user.setHeaderUrl(String.format("http://images.nowcoder.com/head/%dt.png",new Random().nextInt(1000)));
        user.setCreateTime(new Date());
        userMapper.insertUser(user);

        // 发送激活邮件
        Context context = new Context();
        context.setVariable("email",user.getEmail());
        // http://localhost:8080/community/activation/101/code
        String url = domain + contextPath + "/activation/" + user.getId() + "/" + user.getActivationCode();
        context.setVariable("url",url);
        String content = templateEngine.process("/mail/activation", context);
        mailClient.sendMail(user.getEmail(),"激活邮件",content);

        return map;
    }

    /**
     * 点击邮件链接，激活用户
     * @param userId
     * @param code
     * @return
     */
    public int activation(int userId,String code){
        User user = userMapper.selectById(userId);
        if(user.getStatus() == 1){
            return ACTIVATION_REPEAT;
        }else if (user.getActivationCode().equals(code)){
            userMapper.updateStatus(userId,1);
            clearCache(userId);
            return ACTIVATION_SUCCESS;
        }else {
            return ACTIVATION_FAILURE;
        }

    }

    /**
     * 登录业务
     * @param username
     * @param password
     * @param expiredSeconds
     * @return
     */
    public Map<String,Object> login(String username,String password,int expiredSeconds){
        Map<String,Object> map = new HashMap<>();

        // 空值处理
        if(StringUtils.isBlank(username)){
            map.put("usernameMsg","账号不能为空！");
            return map;
        }
        if(StringUtils.isBlank(password)){
            map.put("passwordMsg","密码不能为空！");
            return map;
        }

        // 验证账号
        User user = userMapper.selectByName(username);
        if(user == null){
            map.put("usernameMsg","该账号不存在！");
            return map;
        }
        if(user.getStatus() == 0){
            map.put("usernameMsg","该账号未激活！");
            return map;
        }

        // 验证密码
        password = CommunityUtil.md5(password + user.getSalt());
        if(!user.getPassword().equals(password)){
            map.put("passwordMsg","密码不正确！");
            return map;
        }

        // 生成登录凭证
        LoginTicket loginTicket = new LoginTicket();
        loginTicket.setUserId(user.getId());
        loginTicket.setTicket(CommunityUtil.generateUUID());
        loginTicket.setStatus(0);
        loginTicket.setExpired(new Date(System.currentTimeMillis() + expiredSeconds * 1000));
        // loginTicketMapper.insertLoginTicket(loginTicket);

        String redisKey = RedisKeyUtil.getTicketKey(loginTicket.getTicket());
        redisTemplate.opsForValue().set(redisKey, loginTicket);

        map.put("ticket",loginTicket.getTicket());

        return map;
    }

    /**
     * 退出登录
     * @param ticket
     */
    public void logout(String ticket){
        // loginTicketMapper.updateStatus(ticket,1);
        String redisKey = RedisKeyUtil.getTicketKey(ticket);
        LoginTicket loginTicket = (LoginTicket) redisTemplate.opsForValue().get(redisKey);
        loginTicket.setStatus(1);
        redisTemplate.opsForValue().set(redisKey, loginTicket);
    }

    /**
     * 查询登录凭证对象
     * @param ticket
     * @return
     */
    public LoginTicket findLoginTicket(String ticket){
        // return loginTicketMapper.selectByTicket(ticket);
        String redisKey = RedisKeyUtil.getTicketKey(ticket);
        return (LoginTicket) redisTemplate.opsForValue().get(redisKey);
    }

    /**
     * 更新用户头像（路径）
     * @param userId
     * @param headerUrl
     * @return
     */
    public int updateHeader(int userId,String headerUrl){
        // return userMapper.updateHeader(userId,headerUrl);
        int rows = userMapper.updateHeader(userId, headerUrl);
        clearCache(userId);
        return rows;
    }

    /**
     * 发送邮箱验证码（忘记密码）
     * @param email
     * @return
     */
    public Map<String,Object> sendEmailKaptcha(String email,String text){
        Map<String,Object> map = new HashMap<>();
        // 空值处理
        if(StringUtils.isBlank(email)){
            map.put("emailMsg","邮箱不能为空！");
            return map;
        }
        if(StringUtils.isBlank(text)){
            map.put("codeMsg","验证码发送失败！");
            return map;
        }
        // 验证邮箱
        User user = userMapper.selectByEmail(email);
        if(user == null){
            map.put("emailMsg","该邮箱不存在！");
            return map;
        }
        // 发送邮箱
        mailClient.sendMail(email,"验证码邮箱",text);
        return map;
    }

    /**
     * 找回用户密码（忘记密码）
     * @param email
     * @param password
     * @return
     */
    public Map<String,Object> updatePassword(String email,String password){
        Map<String,Object> map = new HashMap<>();
        // 空值处理
        if(StringUtils.isBlank(password)){
            map.put("passwordMsg","新密码不能为空！");
            return map;
        }
        // 更改密码
        User user = userMapper.selectByEmail(email);
        password = CommunityUtil.md5(password + user.getSalt());
        userMapper.updatePassword(user.getId(), password);
        return map;
    }

    /**
     * 修改用户密码（账号设置）
     * @param user
     * @param oldPassword
     * @param newPassword
     * @return
     */
    public Map<String,Object> updatePasswordByOld(User user,String oldPassword,String newPassword){
        Map<String,Object> map = new HashMap<>();
        // 空值处理
        if(user == null){
            map.put("userMsg","用户未登录！");
            return map;
        }
        if(StringUtils.isBlank(oldPassword)){
            map.put("oldPasswordMsg","原始密码不能为空！");
            return map;
        }
        if(StringUtils.isBlank(newPassword)){
            map.put("newPasswordMsg","新密码不能为空！");
            return map;
        }

        // 验证原密码是否正确
        oldPassword = CommunityUtil.md5(oldPassword + user.getSalt());
        if(!user.getPassword().equals(oldPassword)){
            map.put("oldPasswordMsg","原始密码不正确！");
            return map;
        }

        // 修改密码
        newPassword = CommunityUtil.md5(newPassword + user.getSalt());
        userMapper.updatePassword(user.getId(),newPassword);

        return map;
    }

    // 1. 优先从缓存中取值
    private User getCache(int userId) {
        String redisKey = RedisKeyUtil.getUserKey(userId);
        return (User) redisTemplate.opsForValue().get(redisKey);
    }

    // 2. 取不到时初始化缓存数据
    private User initCache(int userId) {
        User user = userMapper.selectById(userId);
        String redisKey = RedisKeyUtil.getUserKey(userId);
        redisTemplate.opsForValue().set(redisKey, user, 3600, TimeUnit.SECONDS);
        return user;
    }

    // 3. 数据变更时清除缓存数据
    private void clearCache(int userId) {
        String redisKey = RedisKeyUtil.getUserKey(userId);
        redisTemplate.delete(redisKey);
    }

    /**
     * 获取用户的权限(身份)
     * @param userId
     * @return
     */
    public Collection<? extends GrantedAuthority> getAuthorities(int userId) {
        User user = this.findUserById(userId);
        
        List<GrantedAuthority> list = new ArrayList<>();
        list.add(new GrantedAuthority() {
            @Override
            public String getAuthority() {
                switch (user.getType()) {
                    case 1:
                        return AUTHORITY_ADMIN;
                    case 2:
                        return AUTHORITY_MODERATOR;
                    default:
                        return AUTHORITY_USER;
                }
            }
        });
        return list;
    }

}
